Beltane is mentioned in some of the earliest Irish literature and it is associated with important events in Irish mythology. It marked the beginning of summer and was when cattle were driven out to the summer pastures. Rituals were performed to protect the cattle, crops and people, and to encourage growth. Special bonfires were kindled, and their flames, smoke and ashes were deemed to have protective powers. The people and their cattle would walk around the bonfire or between two bonfires, and sometimes leap over the flames or embers. All household fires would be doused and then re-lit from the Beltane bonfire. These gatherings would be accompanied by a feast, and some of the food and drink would be offered to the aos sí. Doors, windows, byres and the cattle themselves would be decorated with yellow May flowers, perhaps because they evoked fire. In parts of Ireland, people would make a May Bush: a thorn bush decorated with flowers, ribbons and bright shells. Holy wells were also visited, while Beltane dew was thought to bring beauty and maintain youthfulness. Many of these customs were part of May Day or Midsummer festivals in other parts of Great Britain and Europe.

Beltane celebrations had largely died out by the mid-20th century, although some of its customs continued and in some places it has been revived as a cultural event. Since the late 20th century, Celtic neopagans and Wiccans have observed Beltane, or something based on it, as a religious holiday. Neopagans in the Southern Hemisphere often celebrate Beltane at the other end of the year (around 1 November).

Beltane was one of four Gaelic seasonal festivals: Samhain (~1 November), Imbolc (~1 February), Beltane (~1 May) and Lughnasadh (~1 August). Beltane marked the beginning of the pastoral summer season, when livestock were driven out to the summer pastures.[5][6] Rituals were held at that time to protect them from harm, both natural and supernatural, and this mainly involved the "symbolic use of fire".[5] There were also rituals to protect crops, dairy products and people, and to encourage growth. The aos sí (often referred to as spirits or fairies) were thought to be especially active at Beltane (as at Samhain)[5] and the goal of many Beltane rituals was to appease them. Most scholars see the aos sí as remnants of the pagan gods and nature spirits.[7] Beltaine was a "spring time festival of optimism" during which "fertility ritual again was important, perhaps connecting with the waxing power of the sun".[2]

Beltane (the beginning of summer) and Samhain (the beginning of winter) are thought to have been the most important of the four Gaelic festivals. Sir James George Frazer wrote in The Golden Bough: A Study in Magic and Religion that the times of Beltane and Samhain are of little importance to European crop-growers, but of great importance to herdsmen. Thus, he suggests that halving the year at 1 May and 1 November dates from a time when the Celts were mainly a pastoral people, dependent on their herds.[8]

According to 17th century historian Geoffrey Keating, there was a great gathering at the hill of Uisneach each Beltane in medieval Ireland, where a sacrifice was made to a god named Beil. Keating wrote that two bonfires would be lit in every district of Ireland, and cattle would be driven between them to protect them from disease.[11] There is no reference to such a gathering in the annals, but the medieval Dindsenchas includes a tale of a hero lighting a holy fire on Uisneach that blazed for seven years. Ronald Hutton writes that this may "preserve a tradition of Beltane ceremonies there", but adds "Keating or his source may simply have conflated this legend with the information in Sanas Chormaic to produce a piece of pseudo-history."[5] Nevertheless, excavations at Uisneach in the 20th century found evidence of large fires and charred bones, showing it to have been ritually significant.[5][12][13]

Bonfires continued to be a key part of the festival in the modern era. All hearth fires and candles would be doused before the bonfire was lit, generally on a mountain or hill.[2][14]Ronald Hutton writes that "To increase the potency of the holy flames, in Britain at least they were often kindled by the most primitive of all means, of friction between wood."[5] In the 19th century, for example, John Ramsay described Scottish Highlanders kindling a need-fire or force-fire at Beltane. Such a fire was deemed sacred.[5] In the 19th century, the ritual of driving cattle between two fires—as described in Sanas Cormaic almost 1000 years before—was still practised across most of Ireland and in parts of Scotland.[5] Sometimes the cattle would be driven "around" a bonfire or be made to leap over flames or embers. The people themselves would do likewise.[5] In the Isle of Man, people ensured that the smoke blew over them and their cattle.[6] When the bonfire had died down, people would daub themselves with its ashes and sprinkle it over their crops and livestock.[5] Burning torches from the bonfire would be taken home, where they would be carried around the house or boundary of the farmstead[15] and would be used to re-light the hearth.[5] From these rituals, it is clear that the fire was seen as having protective powers.[5] Similar rituals were part of May Day, Midsummer or Easter customs in other parts of the British Isles and mainland Europe.[16] According to Frazer, the fire rituals are a kind of imitative or sympathetic magic. According to one theory, they were meant to mimic the Sun and to "ensure a needful supply of sunshine for men, animals, and plants". According to another, they were meant to symbolically "burn up and destroy all harmful influences".[17]

Food was also cooked at the bonfire and there were rituals involving it. Alexander Carmichael wrote that there was a feast featuring lamb, and that formerly this lamb was sacrificed.[18] In 1769, Thomas Pennant wrote that, in Perthshire, a caudle made from eggs, butter, oatmeal and milk was cooked on the bonfire. Some of the mixture was poured on the ground as a libation. Everyone present would then take an oatmeal cake, called the bannoch Bealltainn or "Beltane bannock". A bit of it was offered to the spirits to protect their livestock (one bit to protect the horses, one bit to protect the sheep, and so forth) and a bit was offered to each of the animals that might harm their livestock (one to the fox, one to the eagle, and so forth). Afterwards, they would drink the caudle.[5]

According to 18th century writers, in parts of Scotland there was another ritual involving the oatmeal cake. The cake would be cut and one of the slices marked with charcoal. The slices would then be put in a bonnet and everyone would take one out while blindfolded. According to one writer, whomever got the marked piece would have to leap through the fire three times. According to another, those present would pretend to throw him into the fire and, for some time afterwards, they would speak of him as if he were dead. This "may embody a memory of actual human sacrifice", or it may have always been symbolic.[5] A similar ritual (i.e. of pretending to burn someone in the fire) was practised at spring and summer bonfire festivals in other parts of Europe.[19]

Yellow flowers such as primrose, rowan, hawthorn, gorse, hazel and marsh marigold were placed at doorways and windows in 19th century Ireland, Scotland and Mann. Sometimes loose flowers were strewn at the doors and windows and sometimes they were made into bouquets, garlands or crosses and fastened to them. They would also be fastened to cows and equipment for milking and butter making. It is likely that such flowers were used because they evoked fire.[5] Similar May Day customs are found across Europe.

The May Bush was popular in parts of Ireland until the late 19th century. This was a small tree or branch—typically hawthorn, rowan or sycamore—decorated with bright flowers, ribbons, painted shells, and so forth. There were household May Bushes (which would be placed outside each house) and communal May Bushes (which would be set in a public spot or paraded around the neighbourhood). In Dublin and Belfast, May Bushes were brought into town from the countryside and decorated by the whole neighbourhood.[14] Each neighbourhood vied for the most handsome tree and, sometimes, residents of one would try to steal the May Bush of another. This led to the May Bush being outlawed in Victorian times.[14] In some places, it was customary to dance around the May Bush, and at the end of the festivities it may be burnt in the bonfire.[20] Some, however, were left in place for a month. Thorn trees were seen as special trees and were associated with the aos sí. The custom of decorating a May Bush or May Tree was found in many parts of Europe. Frazer believes that such customs are a relic of tree worship and writes: "The intention of these customs is to bring home to the village, and to each house, the blessings which the tree-spirit has in its power to bestow."[21]Emyr Estyn Evans suggests that the May Bush custom may have come to Ireland from England, because it seemed to be found in areas with strong English influence and because the Irish saw it as unlucky to damage certain thorn trees.[22] However, "lucky" and "unlucky" trees varied by region, and it has been suggested that Beltane was the only time when cutting thorn trees was allowed.[23] The practice of bedecking a May Bush with flowers, ribbons, garlands and bright shells is found among the Gaelic diaspora, most notably in Newfoundland, and in some Easter traditions on the East Coast of the United States.[14]

Holy wells were often visited at Beltane, and at the other Gaelic festivals of Imbolc and Lughnasadh. Visitors to holy wells would pray for health while walking sunwise (moving from east to west) around the well. They would then leave offerings; typically coins or clooties (see clootie well).[14] The first water drawn from a well on Beltane was seen as being especially potent, as was Beltane morning dew. At dawn on Beltane, maidens would roll in the dew or wash their faces with it. It would also be collected in a jar, left in the sunlight, and then filtered. The dew was thought to increase sexual attractiveness, maintain youthfulness, and help with skin ailments.[6][14][20]

People also took steps specifically to ward-off or appease the aos sí. Food was left or milk poured at the doorstep or places associated with the aos sí, such as 'fairy trees', as an offering.[24][25] In Ireland, cattle would be brought to 'fairy forts', where a small amount of their blood would be collected. The owners would then pour it into the earth with prayers for the herd's safety. Sometimes the blood would be left to dry and then be burnt.[24] It was thought that dairy products were especially at risk from harmful spirits.[14][26][27] To protect farm produce and encourage fertility, farmers would lead a procession around the boundaries of their farm. They would "carry with them seeds of grain, implements of husbandry, the first well water, and the herb vervain (or rowan as a substitute). The procession generally stopped at the four cardinal points of the compass, beginning in the east, and rituals were performed in each of the four directions".[28]

The festival persisted widely up until the 1950s, and in some places the celebration of Beltane continues today.[13][26][27]

As a festival, Beltane had largely died out by the mid-20th century, although some of its customs continued and in some places it has been revived as a cultural event. In Ireland, Beltane fires were common until the mid 20th century,[14] but the custom seems to have lasted to the present day only in County Limerick (especially in Limerick itself) and in Arklow, County Wicklow.[29] However, the custom has been revived in some parts of the country. Some cultural groups have sought to revive the custom at Uisneach and perhaps at the Hill of Tara.[30] The lighting of a community Beltane fire from which each hearth fire is then relit is observed today in some parts of the Gaelic diaspora, though in most of these cases it is a cultural revival rather than an unbroken survival of the ancient tradition.[14][31][32] In some areas of Newfoundland, the custom of decorating the May Bush is also still extant.[33] The town of Peebles in the Scottish Borders holds a traditional week-long Beltane Fair every year in June, when a local girl is crowned Beltane Queen on the steps of the parish church. Like other Borders festivals, it incorporates a Common Riding.[34]

Since 1988, a Beltane Fire Festival has been held every year during the night of 30 April on Calton Hill in Edinburgh, Scotland. While inspired by traditional Beltane, this festival is a modern arts and cultural event which incorporates myth and drama from a variety of world cultures and diverse literary sources.[35]

Beltane and Beltane-based festivals are held by some Neopagans. As there are many kinds of Neopaganism, their Beltane celebrations can be very different despite the shared name. Some try to emulate the historic festival as much as possible.[36] Other Neopagans base their celebrations on many sources, the Gaelic festival being only one of them.[37][38]

Neopagans usually celebrate Beltane on 30 April – 1 May in the Northern Hemisphere and 31 October – 1 November in the Southern Hemisphere, beginning and ending at sunset.[39][40][41][42][43] Some Neopagans celebrate it at the astronomical midpoint between the spring equinox and summer solstice (or the full moon nearest this point). In the Northern Hemisphere, this midpoint is when the ecliptic longitude of the Sun reaches 45 degrees.[44] In 2014, this is on 5 May.[45]

Celtic Reconstructionists strive to reconstruct the pre-Christian religions of the Celts. Their religious practices are based on research and historical accounts,[36][46] but may be modified slightly to suit modern life. They avoid modern syncretism and eclecticism (i.e. combining practises from unrelated cultures).[47]

Celtic Reconstructionists usually celebrate Lá Bealtaine when the local hawthorn trees are in bloom. Many observe the traditional bonfire rites, to whatever extent this is feasible where they live. This may involve passing themselves and their pets or livestock between two bonfires, and bringing home a candle lit from the bonfire. If they are unable to make a bonfire or attend a bonfire ceremony, torches or candles may be used instead. They may decorate their homes with a May Bush, branches from blooming thorn trees, or equal-armed rowan crosses. Holy wells may be visited and offerings made to the spirits or deities of the wells. Traditional festival foods may also be prepared.[48][49]

Wiccans use the name Beltane or Beltain for their May Day celebrations. It is one of the yearly Sabbats of the Wheel of the Year, following Ostara and preceding Midsummer. Unlike Celtic Reconstructionism, Wicca is syncretic and melds practises from many different cultures. In general, the Wiccan Beltane is more akin to the Germanic/English May Day festival, both in its significance (focusing on fertility) and its rituals (such as maypole dancing). Some Wiccans enact a ritual union of the May Lord and May Lady.[39]

In Irish, the festival is usually called Lá Bealtaine ("day of Beltane") while the month of May is Mí Bhealtaine ("month of Beltane"). In Scottish Gaelic, the month is called (An) Cèitean or a' Mhàigh, and the festival is Latha Bealltainn. Sometimes the older Scottish Gaelic spelling Bealltuinn is used. The word Céitean comes from Céad Shamhain, an old alternative name for the festival.[citation needed]

In modern Scottish Gaelic, Latha Buidhe Bealltainn or Là Buidhe Bealltainn ("the yellow day of Beltane") is used to describe the first day of May. This term Lá Buidhe Bealtaine is also used in Irish and is translated as "Bright May Day". In Ireland it is referred to in a common folk tale as Luan Lae Bealtaine; the first day of the week (Monday/Luan) is added to emphasise the first day of summer.[citation needed]

Since the early 20th century it has been commonly accepted that Old IrishBeltaine is derived from a Common Celtic*belo-te(p)niâ, meaning "bright fire". The element *belo- might be cognate with the English word bale (as in bale-fire) meaning "white" or "shining"; compare Old Englishbael, and Lithuanian/Latvianbaltas/balts, found in the name of the Baltic; in Slavic languagesbyelo or beloye also means "white", as in Беларусь (White Russia or Belarus) or Бе́лое мо́ре (White Sea). A more recent etymology by Xavier Delamarre would derive it from a Common Celtic *Beltinijā, cognate with the name of the Lithuanian goddess of death Giltinė, the root of both being Proto-Indo-European*gʷelH- ("suffering, death").[50]

In Ó Duinnín's Irish dictionary (1904), Beltane is referred to as Céadamh(ain) which it explains is short for Céad-shamh(ain) meaning "first (of) summer". The dictionary also states that Dia Céadamhan is May Day and Mí Céadamhan is the month of May.

^Aideen O'Leary reports ("An Irish Apocryphal Apostle: Muirchú's Portrayal of Saint Patrick" The Harvard Theological Review89.3 [July 1996:287–301] p. 289) that, for didactic and dramatic purposes, the festival of Beltane, as presided over by Patrick's opponent King Lóegaire mac Néill, was moved to the eve of Easter and from Uisneach to Tara by Muirchú (late 7th century) in his Vita sancti Patricii; he describes the festival as in Temora, istorium Babylone ("at Tara, their Babylon"). However there is no authentic connection of Tara with Babylon, nor any known connection of Tara with Beltane.